Technical Field
The present disclosure relates to minimally invasive surgery, and more particularly, to a system and method for forming a T-shaped surgical clip for occluding a blood vessel.
Background of Related Art
Minimally invasive surgery has grown in popularity in the past decade. Minimally invasive surgery (MIS) allows a surgeon to treat a patient while making only tiny incisions in the patient's body, through which surgical devices called cannulae are inserted. A cannula is essentially a thin, hollow tube through which other surgical tools may be inserted into and withdrawn from the patient's body. Because only a small incision is made in the patient's skin for insertion of a cannula, the patient heals faster and experiences less pain than in the aftermath of conventional surgery, in which larger incisions and tools are used.
In several minimally invasive procedures, blood vessels in a patient are permanently occluded. Two common procedures involving blood vessel occlusion are saphenous vein harvest, in which a vein and its branches are occluded so that a portion of that vein can be removed from one location in the body and used in another, and subfascial endoscopic perforator surgery, in which perforator veins are permanently occluded. In recent years, malleable metal clips or surgical hemostatic clips have been used for permanent occlusion. These clips typically have an opening at one end that is at least as wide as the blood vessel to be occluded. A surgical instrument is inserted through the cannula which places these clips, often serially, in desired locations on blood vessels, then squeezes them shut to achieve permanent occlusion. Such surgical instruments have in the past been bulky enough to require a cannula having an internal diameter of 10 mm or even 12 mm in order to insert them through the cannula to reach the operative site.
Certain factors are important to the performance of a surgical hemostatic clip to achieve proper tissue exudation and occlusion. The clip should not slip or become dislodged from a vessel after it has been applied. If the clip is not securely positioned, blood or other bodily fluid may begin flowing into the surgical site through the unclamped vessel. As a result, a surgeon locates and reclamps the vessel. Depending upon the type and location of the surgery, reclamping the vessel may be difficult, and reduce an overall productivity of the procedure. A clip should fully and completely close about a vein, artery, vessel or other conduit and completely stop the flow of blood or fluid therethrough. A clip that does not completely occlude the blood or fluid flow may have to be removed, thus requiring application of a second clip.
Some surgical hemostatic clips are U-shaped or V-shaped. These clips have a pair of legs joined at one end by an apex or crown and spaced apart at the opposed ends to define a gap between the legs. The desired vessel is introduced in the gap and the legs are compressed. The clip thus occludes the vessel using the legs. The legs have surfaces that contact tissue. These “tissue gripping surfaces” of the hemostatic clip may be made in a manner to improve the occluding functions of the hemostatic clip. The surfaces may also restrict dislocation of the hemostatic clip after it has been applied to the target blood vessel.
However, the legs often have a relatively small tissue gripping surface. Care must be taken when designing such tissue gripping surfaces to ensure that the most productive use of the relatively small tissue gripping surface is made to accomplish the occlusion. A significant aspect of the tissue gripping surfaces is this retention of the hemostatic clip on the tissue. Accordingly, there is a need in the art for an improved surgical hemostatic clip to provide an optimum vessel occlusion and optimal clip retention on tissue during a surgical procedure.